This project focuses upon the discovery of novel, naturally occurring antiviral and antitumor molecules from aqueous and organic solvent extracts of terrestrial plants, marine plants, animals and microorganisms. The research employs bioassay-guided isolation and characterization of active molecules. High-throughput screens to support this process are developed with a focus on critical molecular targets or processes implicated in viral (HIV) or cancer pathogenesis. Peptidic or proteinaceous leads are of interest, as well as non-peptic "small-molecules." Structural elucidation involves use of multiple state-of-the-art technologies including mass spectrometry, NMR, and crystallography. New leads are studied in detail in collaboration with intramural and extramural investigators. Commercial partners are sought as soon as possible to participate in and support the preclinical and clinical development of the most promising leads.